Methylated methylolmelamine as a fixing agent for dyed cotton textiles



Patented Mar. 4, 1947 METHYLATED METHYLOLMELAMINE AS A FIXING AGENT FORDYED COTTON TEX- TILES Richard Seyfarth Schreiber and Herman ElbertSchroeder, Wilmington, Del., assignors to E. I. du Pont de Nemours &Company, Wilmington,

DeL, a corporation of Delaware No Drawing. Application September 9,1942, Serial No. 457,718

1 Claim. (Cl. 8--74) This invention relates to the fixation of dye--carbonamides, oxoamides, thioamides, iminostuffs on textiles. amides(amidines) and sulfonamides.

One of the major problems of the dyer is the The preferred methods ofpracticing this infastness of dyes and particularly with respect tovention involve treating a dyed material with washing. Many attemptshave been made to a monomeric dior poly-N-alkoxymethyl comrender colorssufliciently fast to withstand hot pound in the following manner:

soaping, especially in the presence of small The dyed material is wettedwith a solution amounts of alkali under conditions normally encontainingthe poly(N-alkoxymethyl) compound countered in commercial laundries.This is parand is subsequently dried and subjected to an ticularly truein the case of direct azo dyestuffs 10 elevated temperature for a timesufilcient to for cotton which generally exhibit relatively poor causefixation of the dyestuff. More specifically fastness to washing. Manyprocedures described it is preferred to wet the material with approxiinthe art yield dyeings which are fast to hot mately an equal weight of atreating solution water but not to hot soaping. In other cases, whichpossesses a pH of 3-6.5 and contains 1-20% generally involving the useof condensation prodof the poly(N-alkoxymethyl) compound. After ucts offormaldehyde with such amidic substances evaporation of the solvent todeposit the impregas urea, dicyandiamide and melamine, dyeings nant onand within the fibers, the dye is aflixed of good fastness are produced.Certain processes by heating for a short time at IOU-170 C. The (see forexample U. S. Patents 2,169,546 and material is then removed from theoven, rinsed 2,195,357) employ condensation products of formin water anddried. An alternative procedure aldehyde with aminotriazines and appearto give which is also very effective involves heating dyed pa tial y satsfa t ry r su ts n dye fixation, but cloth in a solution containing from1-10% of the under conditions leading to good dye fixation active agentbased on the weight of the cloth these treatments seriously weaken orembrittle employed and in the presence of a mild acidic textilematerials and often alter the shade of the catalyst, e. g., at a pHbelow 6.5 and preferably color. Since washfastness is generally poorestin above 3.

the case of cotton and other cellulosic materials The more detailedpractice of the invention is which are most easily damaged, suchprocesses illustrated in the following examples, wherein leave much tobe desired. parts given are by weight. There are, of course, Thisinvention has as an object the producmany forms of the invention otherthan these tion of dyeings of the maximum possible fastness specificembodiments. 1

to washing and other wet treatments with a minimum of deleteriou effectson the fabric. EXAMPLE I o er j q s W p QI This example illustrates thefixation of sev- These oblects are accomplished by t f W- eralrepresentative azo dyestuffs which are thereing invention wherein thewash fastness Of a by rendered fast to hot, soap solutions,

dyed textile or flexible organic sheet material A 20% aqueous l t f '..bt

is improved by treatment with a monomeric nimethyl) adipamide (made bythe procedure detro en-cont inin mp n v n at l ast two 40 scribed incopending application of McGrew, nitrogen atoms each of which isattached to a Serial No. 360,835, filed October 11, 1940, now methylene(CH2) group which is in turn U. S. Patent 2,364,737) was prepared bydissolvlinked through an ether oxygen to a monovalent ing 20 parts ofthe agent in 80 parts of water. hydrocarbon radical. There were thenwetted in'the solution samples The preferred materials of the abovegeneral of cotton fabric previously dyed in the usual classification aremonomeric organic compounds, manner with the following representativeazo otherwise free from reactive groups, containing dyestuffs. aplurality of amidic nitrogens having thereon 1. Pontamine Blue BB (ColorIndex No. 406). etherifled methylol groups. By amidic nitrogen 2. A redazo dyestuif prepared by tetrazotizing is meant the nitrogen atom inamides including the l-(p-aminobenzoyl) derivative of 2-methy1- sodiumcarbonate.

p phenylenediamine and coupling to two moles until the gain in weightwas approximately 100% and were then heated for 10 minutes at 125 C.After rinsing, the fastness of the dyeings to washing was ascertained byboiling for 30 minutes in an 0.5% tallowsoap solution containing 0.2% Inevery case the treated dyeings were found to be considerably superior tocontrols, bleeding but slightly and producing no stain on an attachedpiece of silk. A similar treatment of the same dyeings with anadipamideformaldehyde condensation product (dimethyloladipamide)increased the fastness somewhat but the results were in no waycomparable with those obtained using the ether, for the dyeings were notrendered sufiiciently fast and serious changes in shade and spottingwere observed. The results are summarized in the following table.

TABLE I Efiect of agents on fastness of dyeinys to boil wash test a None(control) D D D D $12) Dimethyloladipamide C C 0+ (0)N,N-bis(methoxymethyl) adipamido A B+ A+ A A=excel1ent, B =good, C=fair,l3=poor (control).

EXAMPLE II Viscose rayonyarn which had been rendered basic, e. g., byincorporation of a protein or albuminous material, was dyed in the usualmanner with the acid dyestuff 1-amino-4(p-toluidino)-anthraquinonedisulfonic acid and the fastness improved asfollows: After dyeing, the

skeins were steeped in a solution of N,N'--

bis(methoxymethyl) urea (Kadowaki, Bull. Chem. Soc. Japan 11, 248(1936)) containing 1% ammonium chloride as catalyst and suflicientacetic EXAMPLE III This example illustrates the use of alkoxymethylderivatives of other amides. methylamides were prepared as described incopending application Serial No. 360,835.

Samples of bleached cotton muslin dyed in The alkoxy- 4 the usual mannerwith a blue azo dye (Color Index No. 406) were impregnated with 5%aqueous solutions of the following reagents:

1. N,N'-bis(methoxymethyl)succinamide.

2. N,N'-bis (methoxymethyl) fumaramide.

3. N,N'-bis (methoxymethyl) sebacamide.

The solutions were then vacidified with sufiicient amount of acetic acid'to produce a pH of 2.5. After impregnation; .the samples were wrung outuntil the gain in weight was approximately dried at the ordinarytemperature, and ironed for 30 seconds. 'The dyeiu s thus producedpossessed excellent fastness to boiling soap solution, the bleeding andloss of color being negligible whereas untreated controls were very poorin both respects. I

EXAMPLE IV This example illustrates theuse of the polyalkoxymethylderivative of a cyclic amidine.

Four samples of cotton fabric dyedwith a blue dye (Color Index No. 406)wereimpregnated in 5% aqueous solutions of-N,N',Nf'-tris(methoxymethyDmelamine, prepared by the procedure described in McGrew copendingapplication Serial No. 387,771,-filed April 9, 1941, adjusted to a pH of3.7-3.9 and wrung to 100% gain in weight. After drying at the ordinarytemperature these four samples were heated in an oven for, respectively,(a) four minutes at C., (b) -30seconds I at C., (c) 10 seconds at C.,and (d) 20 seconds at 165 C. After rinsing in cold water these sampleswere all found to be substantially unaffected by boiling in 0.5% soapsolution containing 0.2% added sodium carbonate. Similar treatmentsconducted at pH 4.4-4.5 produced essentially the same results. Theuntreated fabric has very poor fastness.

The superiority of the tris(methoxymethyl)- melamine over themelamine-formaldehyde condensation products may be seen in the followingtable which shows the effect on tensil strength of treatment at varioustemperatures for a time suflicient to obtain substantially the sameexcel-.

lent fixation of the color.

This example illustrates the use of an ethyl ether.

The compound N,N',N"-tris(ethoxymethyl)- melamine was prepared fromtrimethylol melamine according to the procedure of copending applicationSerial No. 387,771. A 5% solution of this reagent in 1:1 ethanol-waterwas then divided into 3 portions to which were added; respectively,suificient glacial acetic acid to produce pHs of 3 and 4; and sufficientsodium acetate to produce a pH of 8.4. Samples of bleached cotton muslindyed in the usual manner with a blue dye (Color Index No. 406) were thenwetted in each of these solutions until the gain in weight wasapproximately 100%, passed through a nip and dried at the ordinarytemperature. These dried samples were then held in an ironing machinefor 30 seconds, rinsed, dried and tested by immersing in boiling soapsolution for 30 minutes. The following results were obtained.

TABLE III Wash fastness to dyeings of Pontamine Blue BB aftertreatedwith N,N',N"-tris(eth.0xymethyl) melamine Treatment with agent at--Control (no agent) pH 3 pH 4 pH 8.4

' D A+ A+ A Ratings: A=excellent, B=good, C=fair, D=poor.

addition spotty. The fixation of the dye was only fair.

The monomeric ethers of trimethylolmelamine. are prepared by stirringtrimethylolmelamine in anhydrous liquid medium with 2 to 5 parts of amonohydric alcohol, preferably of not more than four carbons, e. g.,methanol or ethanol, at a temperature of not mor than 50 C. andpreferably at 0 C. to 25 C., in the presence of an anhydrous acidcondensing agent, until the suspended trimethylolmelamine disappears,neutralizing with the sodium alcoholate of the alcohol used, filteringoff the sodium salt of the condensing agent and isolating the ethervfrom the filtrate.-

' EXAMPLE VI This example illustrates the use of N-alkoxymethylderivatives of cyclic compounds containing the substituted nitrogenatoms in the ring.

Six samples of cotton cloth dyed in the usual manner with the blue dye(Color Index No. 406) were impregnated with the following six solutionswhich with the exception of 3 had acidities in the pH range 3.5 to 4: r

1. An aqueous solution containing 10 parts by weight ofN,N'-bis(methoxymethyl) uron (Bull. Soc. Chem. Japan 11, 248 (1936)), 90parts of water and 5 parts of glacial acetic acid.

2. A similar solution containing 2 parts of glacial acetic acid.

3. A similar solution buffered at ph 5.5 by use of acetic acid andpotassium acetate.

4. An aqueous solution containing 10 parts N,N'-bis (methoxymethyl)ethyleneurea (prepared by applying the procedure described inapplication Serial No. 426,905, filed January 15, 1942, to cause thereaction of dimethylolethyleneurea with methanol), 90 parts of water and2 parts of glacial acetic acid.

5. An aqueous solution containing 10 parts by weight of1,3-bis(methoxymethyl)-5-methyl-striazone(2) ,6 cmocm N-CHI,

o=o 0H;

90 parts water and 2 parts of glacial acetic acid (prepared by theprocedure described in application Serial No. 426,905, filed January 15,1942) 6. An aqueous solution containing 10 parts ofN,N'-bis(methoxymethyl) -5,5-dimethylhydantoin omocm N-'co shC*cc-rL-Cmoom prepared by similar reaction of 5,5-dimethylhydantoin withformaldehyde and then with dry methanol in the presence of dry hydrogenchloride.

The samples were then passed through a nip until the gain in weight wasapproximately 100% and were finally baked in an oven at 125 C. for

5 minutes. Dyeings thus produced were all found to be considerablyimproved in fastness to boiling 0.5% soap solution.

EXAMPLE v11 This example illustrates fixation of dyestufl with anN-alkoxymethyl derivative in aqueous solution.

Two hundred and fifty parts of a 20% sodium chloride solution wasacidified with 1 part of formic acid. The resulting solution'was dividedinto two equal parts which were heated to 80 and 100 C., respectively,when there was added to each 10cc. of a 5% aqueous-solution of N,N',N"-

tris(methoxymethyl) melamine. A portion of bleached cotton muslin (15parts bywei'ght) dyed in the usual manner with a blue dye (Color IndexNo. 406) was then placed in each solution and the solutions maintainedat 80 and 100 C., respectively, for 15 minutes, when the cloth wasremoved and dried. The dyeings thus obtained possessed good fastness toboiling soap solution whereas untreated controls had poor fastness.Analogous treatments with melamineformaldehyde condensation products hadvirtually no effect on the fastness of the dyeing, for resinprecipitated.

. EXAMPLE VIII In this example a number of typical cotton dyestufis areafiixed to the fabric with N,N,N"- tris (methoxymethyl) melamine.

Samples of bleached cotton muslin were dyed in the usual manner with thefollowing colors:

. sulfonic acid.

to washing ascertained in the usual manner inboiling 0.5% tallow soapsolution containing 0.2% of sodium carbonate. In every case the treateddyes were found to be considerably superior to controls, bleeding butslightly. A similar treatment of the same dyeings'with a solution ofthis reagent at a pH of 4.4 produced essentially the same result.

EXAMPLE IX This example illustrates the fixation of dyestuffs to rayon.

Viscose rayon fabric was dyed in the standard manner with the followingcolors:

1. The blue azo dyestuif prepared by coupling diazotizedp-phenylenediamine to l-naphthylamine-G-sulfonic acid, diazotizing andcoupling to 2-amino-7-naphthol-3-sulfonic acid and finally diazotizingand coupling to l-naphthyl-amine-6- EXAIVELE X This example illustratesthe fixation of two representative colors on cellulose acetate.

Samples of cellulose acetate fabric were dyed by orthodox procedureswith the following colors:

1. The yellow azo dyestuff prepared by couplin p-aminoacetanilide top-cresol.

2. The orange azo dyestufi prepared by coupling diazotizedp-nitroaniline to aniline.

The dyed fabric was impregnated as usual with a 10% solution ofN,N',N"-tris(methoxymethyl) melamine, acidified with acetic acid to pHof 4.4 air dried and subsequently baked for 1 minute at 165 C. In thismanner the fastness,

of the dyes to hot or boiling soap solutions was markedly improved.

On dyeing nylon (a synthetic fiber-forming polyamide) with the samecolors and subsequently treating as described above, dyeings wereobtained which exhibited considerably greater fastness to boiling soapsolution than the untreated controls.

Example XI This example illustrates the fixation of dyestufis on wooland leather.

Samples of woven wool and of leather were dyed in the customary mannerwith the following colors:

1. The violet azo dyestufl prepared by cou- 8 pling diazotizedp-phenylenediamine to 1,8-dihydroxynaphthalene-3,6-disulfonic acid.

2. The azo dyestufl prepared by tetrazotizing benzidine and coupling to1 mol of Z-naphthylamine-3,6-disulfonic acid and 1 mol of phenol(p-toluene sulfonated). The wool and leather samples were then wetted inboth 5 and 10% solutions of N,N',N"-tris(methoxymethyl)melamineacidified with acetic acid to a pH of 4.2. After wringing to gain inweight and drying in a current of air, the samples were placed in anoven at C. for 1 minute to insolubilize the color. The woolen dyeingsthus produced were very markedly improved and were substantiallyunaffected by boiling soap solution. Inthe case of leather the sampleswere slightly stiffened but the dyeings were markedly improved, infastness.

The present invention is generic to the use in the fixation of dyestuffsto organic textile materials and flexible organic sheet materials ofmonomeric ethers of poly-(N-methylol) compounds;

These are compounds having at least two nitrogen atoms, each of which isin turn attached to a methylene group which is in turn attached throughan ether oxygen to a monovalent hydrocarbon radical.

A preferred class are monomeric organic compounds, otherwise free fromreactive groups, containing a plurality of amidic nitrogens havingthereon etherified methylol groups. By amidic nitrogen is meant thenitrogen atom in carbonamides, oxoamides, thioamides, amidines, guani,dines, cyclic amides, cyclic amidines, cyclic ureas, su-ifonamides,phosphonamides, etc.

Because of the favorable results obtained the preferred specific classesof monomeric ethers of poly-(N-methyloDamidic substances are themonomeric ethers of poly-(N-methylol)amides, including amidines andthioamides, of polybasic organic acids otherwise free from reactivegroups. The etherified poly-(N-methylol) carbonic acid amides, i. e.,amides of carbonic acid such as me]- amine, urea, and substituted ureas,are particularly preferred.

Because of the ease of preparation it is preferred to use monomericpoly-(N-methylol) compounds etherified with an alkanol of from 1-5carbon atoms and having at least one hydrogen on the carbinol atom. TheN-methoxy-methyl compounds of amides are particularly preferred.

Illustrative poly-(N-methyloDethers in addition to those employed in theexamples are:

N,N-bis(phenoxymethyl) adipamide N,N' -bis (alpha-naphthoxymethyl) ureaN,N' ,N' '-tris (cyclohexyloxy'methyl) melamine N.N,N' -trisallyloxymethyl) melamine N N-bis(butoxymethyl) adipamide N.N' ,N' -tris(methoxymethyl) tricarballylamide N.N'-bis (isopropoxymethyl) urea N,N',N' ,N' tetrakis (methoxymethyl) methylenediurea N,N' -bis(methoxymethyl) biuret CHaOCHzNHCONHCONHCHzOCI-IaN,N',-bis(methoxymethyl) adipic dihydrazide c1130 CHa-N-C o(CH2)A"'0o'NH-CH20 on,v 111E: NH: N,N'-bis (methoxymethyl) dicyandiamideNH NCNV(LJNHCH:O CH:

ch10 on;

N,N'-bis (benzyloxymethyl) urea N,N'-bis(methoxymethyl) terephthalamide9 N,N -bis (methoxymethyl) hydantoin N,N'-bis (ethoxymethyl) thioureaN,N-bis(methoxymethyl)adipohydroxamic acid N,N -bis (methoxymethyl)guanidine NH omo CHzNH-(-NH-CHzO Ha N,N ,N' -tris (methoxymethyl)phenylblguanide i i C oHsNC-N--CNH CHnO C Ha CHaO H: H2OCH3 N,N -bis(methoxymethyl) dithiooxamide The useful compounds of this inventionpossess the properties of homogeneity, and constancy of composition andmolecular Weight. When solid, they are generally crystalline materialsof definite molecular weight or distillable liquids. They differ fromthe resinous or syrupy materials, indefinite in chemical composition andphysical properties, frequently described in the art as being obtainableby heating in alcohol the condensation products of aldehydes with amidicsubstances. The products employed in the process of this invention arehighly reactive materials which are harmed by such treatment. They arebest prepared by reaction of a dry methylol compound with an absolutealcohol in the presence of a dry acidic catalyst at low or moderatetemperatures.

A further advantage of the ethers of poly-(N- methylol) compounds overthe resinous materials described in the art and over the methylolcompounds themselves is the surprising fact that the desired dyefixation reaction is much more readily controlled and superior effectsobtained. Fundamentally, two reactions may be visualized, a dye fixationreaction and resinification, the latter a disadvantageous side reactionwhich competes with the dye fixation for active groups. Dye fixationproceds much more smoothly with less attendant side reactions withetherified N- methylol compounds than with the methylol compoundsthemselves or the resinous condensation'products, both of which eitherby resinification or by being already resinous give rise to otherundesirable effects. Furthermore, the monomeric ethers possess a greaternumber of active groups per unit weight than the resinous materials,since none of the potentially active substituents are dissipated information of the condensation product prior to dye fixation.

The present invention is generic to the fixation, by ethers ofpoly-(N-alkylol) compounds, of soluble dyestuffs, including solublederivatives of insoluble dyestuffs and dyestuff intermediates. Dyestuffsintermediate products may also be affixed. In this manner, materialsnormally possessing little or no affinity for the dyeing agent may becolored by the process of this invention. Suitable dyestufis whosefastness to wet treatments is improved by this treatment includedyestuffs in all groups, such as, acid dyestuffs, direct dyestuffs,basic dyestuffs, pigment dyestuffs, sulfur or vat dyestuffs. Thesedyestufis may belong to the azo, anthraquinone, indigo, or thioindigo,azine or oxazine, azothine, nitro, stilbene, or triphenyl methaneseries. The treatment of direct dyes is of particular importance becauseof the generally poor fastness of these dyes as a class.

If it is desired, instead of the finished dyestuif, intermediateproducts in solubilized form (including true or colloidal solutions) maybe fixed on the fiber. Among such dyestuff intermediate products arematerials which may be converted into dyestuffs by known reactions.These materials are coupling components, diazotization components,compounds which form colors by condensation reactions, etc. While it ispossible to improve the washfastness of any dyestuff' soluble ordispersible in aqueous solutions by treatment with ethers ofpoly-(N-alkylol) compounds, it is preferred that the dyestufl orintermediate contain active groups such as OH SH, NHz, NHR, CONH, CONHR,SO2NH2. SOzNHR or active positions, e. g., nuclear hydrogens activatedby OH, OCHs, NH2, NHR, NR2, etc., or methylene groups rendered active bybeing adjacent to a negative substituent such as carbonyl, sulfonyl, ornitro groups.

The invention embraces the fixation of the dyestuff to any organictextile material or flexible organic sheet material. There may beemployed textiles in any form including single filaments, yarns orfabrics and. textiles from either staple or continuous fibers. Suitabletextile materials and natural fibrous materials include wood pulp,cotton, linen, ramie, hemp, jute. wool. silk. and hair and syntheticorganic fibers such as are derived from superpolyamides, vinyl polymers,casein, zein, soya protein, cellulose ethers, cellulose esters, e. g.,cellulose acetate. and cellulose. Regenerated cellulose rayons producedby any process, e. g., viscose, cuprammonium, etc. are included.

The process is not limited to any particular method of impregnation ortreatment. Thus. the textile may be wetted with a solution of the agentand the dyestuff fixed by subseouent heating. In addition. it isgenerally possible to conduct the impregnation and fixation as asimultaneous operation by heating the textile in a solution of thereagent. In some cases it is possible to treat the textiles with a meltof the poly-(N-alkoxymethyl) compound containing no solvent. However, itis generally most convenient and preferred'to use a solution of theimpregnating agent. conducting the finishing treatment at the same timeor in a later operation. The most effective solvents comprise water,alkanols of from 1-4 carbon atoms and their ether substitutedderivatives. Where cellulosic materials are treated, water is anespecially preferred solvent since its capacity for swelling cellu oseprobably facilitates introduction of the N-alkoxymethyl compound intothe cellulose fiber.

The concentration of the impregnant in the treating solution may varywidely. As may be seen from the examples. it is po sible to achieveuseful effects by employing solutions whose concentration ofN-alkoxymethyl compound is 1% or less. Conversely, the upper limit ofconcentration which may be employed is determined solely by thesolubility of the agent in the medium. In general, it is preferred touse treating solutions containing from 1 to 20% by weight of the imprenant.

Although it is generally most convenient to carry out the impregnationat the ordinary temperatures, the operation may be performed at any i 11temperature between the freezing point and boiling point of theimpregnating solution. It is not necessary to prolong the impregnationstep greatly. In fact, it is usually suflicient to merely wet thetextile material with the impregnating solution. With materials whichare difiicultly wetted, e. g., non-cellulosic textiles, it may bedesirable to use a relatively high temperature of impregnation and toprolong the process somewhat to facilitate swelling of the fibers andthe diffusion of the modifying agents into them. Added substances suchas wetting, softening and swelling agents may, of course, be used toobtain this efiect. I

Although the process of this invention may be carried out under acidicneutral or basic conditions," e. g., a pH of 2-9, it is generallypreferable to operate in the presence of an acidic material. A widevariety of substances producing a pH in the range from 2 to 6.5 areparticularly efiective. If the pH is too low, e. g., below 2, damage tothe textile may ensue, especially if the latter is of cellulosic nature.For best results with regard to rate of reaction and subsequentcondition of the textile, it is preferred to operate in a. pH rangebetween 3 and 6.5. The acidic catalyst need not be present in theimpregnating solution but may be introduced separately, for example by(1) impregnating the textile with acid before employing thepoly-(N-alkoxymethyl) compound,

(2) introducing the acidic material from a second bath subsequent to'theapplication of the impregnant, (3) introducing the acid in the anhydrousform as by exposing the textile to acidic vapors. It is also possible toemploy catalysts which are not actively acidic but are potentially so,for example, operable catalysts include nearly neutral ammonium saltssuch as ammonium chloride and ammonium acetate which become acidic atthe higher temperatures encountered during the dye fixation.

The fixation of various types of dyestufls with poly- (N-alkoxymethyl)compounds usually oc-v curs at temperatures above 40 C., the exact ratebeing determined by the particular substance employed and to a largeextent by the pH of the material. .Thus, at pHs as low as 3 to 4 the dyefixation reaction occurs with practicable rapidity at temperaturesbetween 40 and 100 C. At less acidic pHs, e. g., 5 to 6.5, it is usuallydesirable to use temperatures above 100 C. preferably from 100-165 C.Naturally the highest temperature which may be used is that just belowwhich the textile itself suffers damage by heat. This temperature varieswith the nature of the fiber, for example from about 180 C. for

cellulose ester fibers to about 230 C. for superpolyamide fibers. At thetemperature usually employed, e. g., 100-150 C., durations of from 10seconds to 5 minutes are usually suflicient for the heat treatment,although longer periods may be employed. In general, more prolongedtreatments are desirable or necessary only when the fixation is carriedout at temperatures below 100 C. For example, when the dye fixation isconducted entirely in solution at 80-100 C. it is usually necessary toheat for 3 to 20 minutes.

The utility of this invention lies in the 'production of colored textilematerials possessing superior fastness to wet treatments whichare rtherefore useful in a wide variety of applications,

e. g., in garments where such properties are very desirable.

The treatment of textiles per se with monomeric ethers ofpolymethylolcarbonamido compounds forms the subject matter of copendingMcGrew application Serial No. 410,484, filed September 11, 1941.

The above description and examples are intended to be illustrative only.Any modification of or variation therefrom which conforms to the spiritof the invention is intended to be included within the scope of theclaim.

What is claimed is:

Process for increasing the wash fastness of a dyed cotton textilematerial which comprises heating the dyed material with monomeric N,N,N''-tris(methoxymethyl) melamine, said cotton textile material being dyedwith blue dye Colour Index No. 406.

RICHARD SEYFARTH SCHREIBER HERMAN ELBERT SCI-IROEDER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,169,546 Widmer et al Aug. 15,1939 2,197,357 Widmer'et a1. Apr. 16, 1940 2,203,492 Evans June 4, 19402,033,836 Lantz Mar. 10, 1936 2,254,001 Conaway Aug. 26, 1941 2,329,622Johnstone Sept. 14, 1943 2,339,203 Stiegler Jan. 11, 1944 2,357,273Thurston Aug. 29, 1944 2,248,696 Cassel July 8, 1941 FOREIGN PATENTSNumber Name 7 Date 486,519 British May 30,1938 486,577 British May 30,1938

